--Students should devote most of their time to studying rather than playing computer games

问题补充：

--Students should devote most of their time to studying rather than playing computer games.

---. No pains, no gains.

A. Extremely

B. Actually

C. Obviously

D. Exactly

答案：

A. Extremely

B. Actually

C. Obviously

(答案→)D. Exactly

解析：考查副词辨析。A尤其，特别；B实际上；C明显地；D确切地，精确地；句意:学生应该把所有的时间放在学习上，而不是打游戏。—确实如此，不劳无获。根据句意说明D正确。